This invention relates in general to apparatus for sensing radiation such as X-rays and, more particularly, relates to a large solid state X-ray sensor assembly formed of smaller solid state X-ray sensor assemblies in which blind non detector regions are eliminated.
X-ray detection systems are used widely in medical and industrial applications to image the interior of a structure in a non-invasive manner. Typically, an X-ray system includes a source of X-rays, which are directed to penetrate a region of interest of an object, and X-ray sensitive film which forms an image of the irradiated region of the object. The latent image in the film must be developed before it is available for examination and diagnosis. In order to simplify and speed up the X-ray examination system, various electronic detection systems have evolved. Older systems have utilized scintillators or other X-ray sensitive devices to convert an X-ray image into a visible image. The visible image is then detected by means of an array of Photomultiplier tubes or a cathode ray tube to convert the visible image into an electrical image representative of the X-ray image. The electrical image may then be processed electrically to enhance, display or store the image.
More recently, solid state semi conductor sensors have replaced photomultiplier tubes and cathode ray tubes as visible image detectors. The solid state sensors are combined with X-ray sensitive phosphors or X-ray sensitive image intensifier arrangements. However, the sequential conversion of an X-ray image into a visible image and then to an electrical image is disadvantageous because of reduced sensitivity and resolution as compared to a system which is capable of directly converting an X-ray image into a corresponding electrical image. Moreover, currently available solid state or cathode ray tube X-ray systems are not large enough to image the area of the largest X-ray film. Thus, the frequently used chest X-ray film has a 14.times.17 inch size whereas present day single crystal semi conductor solid state sensors are considerably smaller in size.
There is also a need for a simple, inexpensive and large solid state sensor assembly which senses other types of radiation (such as light) than X-rays.